The present invention relates to a bimorph mirror. A bimorph mirror is conventionally made by superposing two piezoelectric ceramics, and at least one control electrode is placed at the interface between the two ceramics to vary the curvature of the mirror as a function of an electrical voltage applied to the piezoelectric ceramic. As a result, the thinner the mirror, the greater the variation in its radius of curvature.
In addition, ceramic fabrication suffers from limitations concerning the maximum width that can be obtained, with the consequence that it is necessary to build up assemblies with ceramic segments, thereby influencing the stiffness and/or the stability of the bimorph mirror. In particular, stiffness and stability are parameters that are important for the mirror polishing that necessarily takes place after the bimorph mirror has been assembled.
An object of the invention is to provide a bimorph mirror presenting stiffness that is greater than that of a prior art mirror.
Another object of the invention is to provide a bimorph mirror presenting stability that is greater than that of a prior art mirror.
Yet another object of the invention is to provide a bimorph mirror that is capable of being made with large dimensions, for example of meter order.